What is the use of defining a box for drawbead?

If a draw bead box is defined, only the elements inside the box will be
considered in the contact search. All elements in the model will be
searched otherwise.

It is highly recommended to define a boxid around the drawbead to
limit the size of the master surface considered for the draw bead. This
will substantially reduce cost and memory requirements. Care should be
taken to ensure that the box encloses all possible elements when might
come into contact with the drawbead beging considered.